Apparatus for steering a ship

ABSTRACT

A ship is steered by means of a stream of water discharged from a passage branching from a flow passage from a point downstream of an impeller mounted within the flow passage. The flow passage opens onto the surface of the hull so that water is drawn into the flow passage and pumped through the branch passage by means of the impeller. The portion of the branch passage adjacent the discharge opening converges toward the opening and may be closed by a needle valve member positioned within the branch passage opening. The needle valve member may be movable or the convergent portion of the discharge passage may be provided with a movable shroud which slides axially with respect to a fixed needle member to adjust the stream of water discharged therefrom.

United States Patent [191 Hofmann Feb. 20, 1973 [54] APPARATUS FOR STEERING A SHIP [75] Inventor: Alexander llolmann, Heidenheim (Brenz), Germany [73] Assignee: Flrma J. M. Voith GmbH,

Heidenheim, Germany [22] Filed: Feb. 25, 1971 [21] Appl. No.: 118,618

[30] Foreign Application Priority Data Feb. 27, 1970 Germany ..P 20 09 332.7

[52] US. Cl ..114/151 [51] Int. Cl. ..B63h 25/46 [58] Field ofSearch ..ll4/l5l; 115/12 [56] References Cited UNITED STATES PATENTS 3,302,605 2/1967 Kuethur ..l l5/l2 R 3,557,736 1/1961 Baer 3,424,121 1/1969 Thomas et a1. ..1l4/l51 Primary Examiner-Trygvc M. Blix Attorney-Edmund M. Jaskiewicz [57] ABSTRACT A ship is steered by means of a stream of water discharged from a passage branching from a flow passage from a point downstream of an impeller mounted within the flow passage. The flow passage opens onto the surface of the hull so that water is drawn into the flow passage and pumped through the branch passage by means of the impeller. The portion of the branch passage adjacent the discharge opening converges toward the opening and may be closed by a needle valve member positioned within the branch passage opening. The needle valve member may be movable or the convergent portion of the discharge passage may be provided with a. movable shroud which slides axially with respect to a fixed needle member to adjust the stream of water discharged therefrom.

4 Claims, 7 Drawing Figures APPARATUS FOR STEERING A SH]? The present invention relates to an apparatus for steering a vessel by means of a jet of water discharged therefrom, more particularly, to the structure at the discharge opening for adjusting the discharged stream of water.

One form of a steering apparatus for a ship comprises a pump impeller permanently installed in a flow passage to generate a stream of water which is then adjusted by valve means. Such a steering apparatus has been described as an active rudder and may be provided with a T-shaped or Y-shaped passage whose inlet is in the bow of the ship and is oriented with the longitudinal axis of the ship. Downstream of the pump impeller which is mounted within the passage the flow passage may be branched into a single passage extending transversely across the hull of the ship or diverge into two discharge passages which open onto the port and starboard sides of the ship. A gradual curved surface connects the discharge opening with the flow passage and the discharge openings of the passages may be individually controlled by pivotably mounted valve members or other forms of closure members.

Such a steering arrangement has also been mounted in a bulbous bulge extending from the hull of the ship, usually but not limited to from the bow of the ship. The discharge passages have been provided with a pivotably mounted valve flap member for closing the passage and generally extending in the direction of flow when the valve member is opened but closing tightly the passage when the flap is in the closed position.

Such an active steering apparatus has also included a pump impeller of the type having an axial inlet but which discharges a stream of water substantially therefrom by means of vanes in the outlet passage of the pump. The pump flow can further be deflected by a casing which is pivotable around the rotary axis of the pump and has a discharge opening which can be moved into a desired direction. This casing may be a volute or a tubular shroud. The discharge opening of the, shroud is then brought into alignment with a corresponding discharge opening in the bulge when this arrangement is used for steering. Various forms of curved passages or vanes which are pivotable about the axis of rotation of the pump and cooperating with a purely axial flow pump impeller have also been employed as control valves for the discharge passages.

In order to obtain the best possible steering effect with this type of apparatus it is necessary that the valve means be pivotable through an angle of 180 if the discharge passage is disposed in a horizontal plane. For the pivoting drive it has been proposed to use a hydraulic or servo motor whose piston rod acts upon the valve means. It is therefore necessary to provide various forms of transmission members such as a gear mounted co-axially on the valve and driven by a rack coupled to the piston rod to pivot the valve means to the desired angle of 180. Such valve means were pivoted through any desired angle by means of a suitable electric motor and a reduction gear drive. However, this type of a drive is not as sensitive in operation as a hydaulic or pneumatic servo motor. Where the valve means are pivoted directly by means of a lever pivotably connected to the piston rod of the servo motor it is generally necessary that the pivoting angle is substantially smaller than 180 and preferably about The discharge passages for such a steering apparatus have also been positioned to extend downwardly with respect to the axis of rotation of the impeller pump.

While the above structures have been generally satisfactory in operation difliculties have been encountered in obtaining a precise control over the stream of water discharged from a discharge passage.

It is therefore the principal object of the present invention to provide a novel and improved steering apparatus for a ship.

It is another object of the present invention to provide an improved steering apparatus for a ship of the type wherein streams of water are discharged from a passage to obtain the steering effect.

It is a further object of the present invention to provide a novel and improved structure at the discharge opening for such a steering apparatus to control the stream of jet of water discharged therefrom.

The present invention essentially comprises an apparatus for steering a ship in which a pump impeller to generate a stream of water is mounted within a flow passage which has one end opening on the surface of the hull of the ship to define an inlet of water. A branch passage connects to a flow passage downstream of the impeller and has an opening in the hull surface from which the generated stream of water is discharged. A portion of the branch passage adjacent its discharge opening converges toward the opening. An elongated means which may comprise a needle valve member is mounted within the branch passage at the opening. Means are provided for moving either a tubular shroud at the convergent discharge opening or the needle valve member relative to the other so as to adjust the stream of water discharged from the opening and to close the opening.

There may be two branch passages diverging from the flow passage downstream of the impeller means with each branch passage opening being provided with a needle valve member. In its closed position a conical surface of the member will engage the corresponding converging surface of the branch passage while in the open position the jet or stream of high energy content will be produced and discharged from the opening to produce a significant effect.

Other objects and advantages of the present invention will be apparent upon reference to the accompanying description when taken in conjunction with the following drawings, which are exemplary, wherein;

FIG. 1 is a transverse sectional view taken along the line [-1 of FIG. 2 of a branch conduit positioned in a bulge mounted on a lateral portion of the hull of the ship;

FIG. 2 is a longitudinal sectional view taken along the line ll-II of FIG. 1;

FIG. 3 is a sectional view of a bulb on the bow of a ship taken along the line IlI-Ill of FIG. 4 and illustrating a substantially T-shaped discharge passage in which the present invention is incorporated;

FIG. 4 is a longitudinal sectional view taken along the line IV-IV of FIG. 3;

FIG. 5 is a sectional view similar to that of FIG. 1 and taken along the line I-I of FIG. 2 and showing a modification of the discharge opening and needle valve for adjusting the stream of water therethrough;

FIG. 6 is a sectional view similar to that of FIG. 3 and taken along the line VI-VI of FIG. 7 and showing a modification of a discharge passage arrangement similar to that of FIG. 4; and

FIG. 7 is a longitudinal view taken along the line VII-VII of FIG. 6;

Proceeding next to the drawings wherein like reference symbols indicate the same parts throughout the various views a specific embodiment and modifications of the present invention will be described in detail.

As may be seen in FIGS. 1 and 2 a hollow bulge or bulb 2 is attached to the outer surface 1 of the hull of a ship and has mounted therein a flow passage with one end 4 opening toward the bow of the ship to define a inlet for water therethrough. The other or inner end of the duct is curved at 3. The flow passage 5 is substantially longitudinal with respect to the ship and is oriented with respect to the longitudinal axis of the ship.

The passage 5 between inlet 4 and curved end 3 is substantially cylindrical and has mounted therein a pump impeller 6 driven by a drive shaft 7 from a prime mover which is not illustrated. The curve passage 3 is bent at substantially right angles downstream of the pump impeller 6 and has attached thereto a discharge passage 8 with a discharge opening 9 on the outer surface of the bulge 2. That portion of the discharge passage 8 inwardly of the discharge opening 9 is convergent to define a constricted nozzle opening but has a circular cross section.

A needle valve member 10 which is slideably mounted for axial movement within the discharge opening is substantially cylindrical but it is provided with a conical front end which is engageable with the convergent surface adjacent the discharge opening when the needle valve is in the closed position as shown in FIGS. 1 and 2. The large diameter of the valve member 10 is slightly greater than the inner diameter of the discharge opening 9. Preferably, the inner end of the valve member 10 is also conical as shown in the drawings.

The inner end of valve member 10 is provided with an extension on the end of which is mounted a double acting hydraulic piston 11 slideably positioned in a closed pressure cylinder 12. Fluid pressure lines 13 and 14 connect to the cylinder 12 at both ends thereof so as to introduce a fluid under pressure to both sides of the piston 11. The introduction of fluid under pressure within the cylinder causes an axial movement of the piston 11 and accordingly an axial movement of the valve member 10. The movement of the valve member within the discharge opening thus adjusts the stream of fluid generated by pump impeller 6 and discharged from the opening 9. Such a stream will be generated when the valve member is in an open position or moved inwardly from its closed position as shown in FIGS. 1 and 2.

The discharge of a stream of water from the discharge opening 9 will cause a lateral force to act upon the ships hull in a direction opposite to the flow of the stream. This force is sufficient to exert significant steering effect on the ship.

A similar bulge is mounted on the opposite side of the hull of the ship in mirror relationship to the bulge shown in FIGS. 1 and 2.

Proceeding next to FIGS. 3 and 4 there is illustrated a modification wherein the active steering apparatus is constructed in a bulb or bulbous enlargement extending forwardly from the bow of a ship and the flow passage is provided at its inner end with diverging discharge passages opening on the outer surface of the hull. In this modification a circular cylindrical flow passage 25 has a central inlet opening 24 forward end of a bulb 22 at the bow of the ship. An axial pump impeller 26 driven by a drive shaft 27 from a power source which is not shown is positioned in the passage 25. The inner end of the passage 25 downstream of the impeller 26 curves into a T-shaped flow duct 23 having discharge passages 21 and 21 which are curved outwardly and downwardly of the bulb 22 and have discharge openings 29 and 29' on the outer surface thereof. Inwardly of the discharge openings 29 and 29 there are provided converging nozzle shaped constrictions 28 and 28'. The discharge openings 29 and 29' are positioned below a horizontal plane passing through the axis of rotation of the pump impeller 26 as will be apparent as shown in FIG. 3.

The discharge passages 21 and 21 are aligned with each other to have a common longitudinal axis along which two conical valve members 30 and 30' are slideably mounted to move under the action of hydraulic servo motors 32 and 32'. The servo motors 32 and 32 are mounted in a common cylindrical housing which is then sub-divided into pressure cylinders in a manner known in the art which is not shown. The construction of the servo motors 32 and 32' corresponds to the construction of the servo motor comprising piston 1 1 and pressure cylinder 12 as described and illustrated above in FIGS. 1 and 2. A pressure medium is supplied to the servo motors 32 and 32 through pressure lines 33 and 33' and 34, 34' or is discharged therefrom as the case may be in order to move the valve members 30 and 30' in the desired direction.

The valve member 30 is illustrated in the closed position and the valve member 30' is shown in the fully opened position in FIGS. 3 and 4 so that the pump impeller 26 generates a stream of water directed toward the starboard which causes the ship to move to port. As an alternative to the operation of the valve members 30, 30' by their own servo members 32, 32' respectively, a simplied modification may comprise both valve members fixedly coupled to each other by a common rod and for a single double acting piston mounted on the rod to slide within a pressure cylinder.

The construction of FIGS. 3 and 4 can be furthermodified so that the longitudinal axes of the discharge openings are in alignment with each other and intersect or are very closely spaced from the axis of rotation of the impeller.

In FIG. 5 there is illustrated a modification of the structure of FIGS. 1 and 2 wherein a bulge is mounted laterally on the outer surface 41 of the hull of the ship with a longitudinal flow passage 43 similar to the corresponding structural elements in FIGS. 1 and 2. At its inner end the flow passage 32 connects to a discharge passage 52 having a nozzle-shaped constriction 48. The end of the discharge passage is provided with v a discharge opening 49 on the outer surface of the bulge 42. A valve member 50 is constructed in the form of aneedle valve and has a hollow interior which comprises a pressure cylinder as a element of a servo motor in which there is positioned a piston 51 fixedly mounted on the wall of the passage 43. Pressure medium lines 53, 54 for operating the servo motor are positioned in the rod-like element upon which the piston 51 is constructed and in a rib of the flow passage 43. The pres sure lines 53, 54 open on opposite sides of the piston 51 so as to cause movement of the needle valve member 50 when a fluid under pressure is introduced. While the adjusting means is preferably constructed as a hydraulic or pneumatic servo motor it may also be electrically or mechanically driven.

In the modification of FIGS. 6 and 7 a flow duct 63 is constructed within a bulb 62 extending forwardly from the bow of the ship. A central inlet opening 64 forms the inlet for a circular cylindrical passage 65 having mounted therein an axial pump impeller 66 driven by a drive shaft 67 from a source of power which is not shown. Downstream of the impeller 66 the flow passage 65 diverges into discharge passages 61, 61. These discharge passages are so positioned with respect to the inlet passage 65 that the longitudinal axes of the discharge passage when projected on a vertical plane passing perpendicularly to the axis of rotation form angles of approximately 65 with the vertical. When the longitudinal axes are projected onto a horizontal plane which coincides with or is parallel to the axis of rotation of the impeller, each forms an angle or approximately 60 with the axis of rotation of the pump and impeller'so that each discharge opening is oriented at an angle rearwardly and downwardly with respect to the flow passage 65.

Needle-shaped hollow closing or valve members 60,60 whose longitudinal axes coincide with the longitudinal axes of the respective discharge passages 61,61 are mounted fixedly in the housing of the bulb 62 on both sides of drive shaft 67. The walls of the discharge passages 61,61 are each provided with a annular zone having a diameter greater than that of the inner diameter or width of the passage and these zones function as servo motors 72,72. The outer ends of the discharge passages 61,61 converge so as to be constricted in the shape of nozzles 68,68 and are constructed as shrouds which are slideably mounted in the walls of the respective discharge passages. The ends of the shrouds directed toward the drive shaft 67 are provided with annular pistons 71,71 slideable in the servo motors 72,72 respectively. The entire annular piston and shroud assembly is thus axially slideable in the expanded zone of its respective discharge passage. The tubular shrouds 68,68; are provided respectively with circular cylindrical extensions 75,75 each having an opening corresponding to the inner width of the discharge openings 69,69. When in the closed position, the extensions 75,75 are flushed with the outer surface of the bulb 62 and in the open position project outwardly of the outer surface of the bulb 62 by the amount of the piston stroke of its servo cylinder 72 as shown in FIG. 7. The fluid stream emerging from the discharge opening 69 of the discharge passage 61 is thus prevented from emerging against the outer surface of the bulb 62 because the tubular end 75 of the shroud projects outwardly beyond this outer surface.

As result of the construction of FIGS. 6 and 7 the needle valve member can be constructed to have the smallest possible diameter since the adjusting structure is not within the valve member and, at the same time, the slideable shroud can be constructed with the adjusting structure which moves the shroud outwardly to open the discharge opening. When the shroud is constructed so that its outer end is flush with the adjoining surface of the ships hull when the discharge passage is closed, the leading edge of the shroud will move outwardly of the hull surface when the discharge passage is open. This will eliminate the discharged fluid jet from merging on the ships surface even when the ship is travelling at a speed of several knots. As result, the jet of water will be discharged from the discharge opening directly into the surrounding water to provide a significant steering efiect which greatly increases the rudder action of such a steering apparatus.

Thus it can be seen that the present invention has disclosed a fluid jet steering apparatus for a ship wherein the stream of water is adjusted by means of a needle valve member positioned within the discharge opening. The valve member and wall of the discharge opening are movable relative to each other both to open and close the discharge opening and to adjust the intensity of the stream of water discharged therefrom. The steering apparatus may comprise a single discharge passage connected to the inlet flow passage downstream of the pump impeller or a plurality of discharge arrangement with respect to the inlet passage.

It is understood that this invention is susceptible to modification in order to adapt it to different usages and conditions and, accordingly, it is desired to comprehend such modifications within the, invention as may fall within the scope of the appended claims.

What is claimed is:

1. In an apparatus for steering a ship, the combination of a flow passage disposed in a bulb enlargement which extends forwardly from the bow of the ship, the flow passage having one end opening on the surface of the hull at the bow of a ship to define an inlet channel for water, impeller means within said flow passage to generate a stream of water, two branch channel passages communicating with said flow passage downstream of said impeller means and each branch channel passage having an opening in the hull surface to discharge a stream of water therefrom, said branch channel passage converging toward its discharge opening, elongated means within each of said branch channel passages at the discharge openings thereof, and means for moving said converging branch channel passage opening and said elongated means relative to each other in order to open and close the discharge opening.

2. In an apparatus as claimed in claim 1 wherein said elongated means comprises needle valve member which is hollow and is slidably supported on a fixed piston, and means for alternatingly introducing fluid under pressure on both sides of said piston within said valve member to move the same.

3. In an apparatus as claimed in claim 1 wherein the longitudinal axes of the branch passages each defines an acute angle with the axis of rotation of the impeller means when projected on both a vertical plane which is perpendicular to said axis of rotation and a horizontal plane parallel to the axis of rotation.

4. In an apparatus as claimed in claim 1 wherein said converging discharge opening comprises anaxially movable shroud which in the closed position with the extension is flush with the outer surface of the bulb and in the open position projects outwardly of the outer surface of the bulb by the amount of the piston stroke of a servo cylinder and said elongated means is fixed within said branch passage whereby said shroud is movable with respect to said elongated means in order to open or close the discharge opening. 

1. In an apparatus for steering a ship, the combination of a flow passage disposed in a bulb enlarGement which extends forwardly from the bow of the ship, the flow passage having one end opening on the surface of the hull at the bow of a ship to define an inlet channel for water, impeller means within said flow passage to generate a stream of water, two branch channel passages communicating with said flow passage downstream of said impeller means and each branch channel passage having an opening in the hull surface to discharge a stream of water therefrom, said branch channel passage converging toward its discharge opening, elongated means within each of said branch channel passages at the discharge openings thereof, and means for moving said converging branch channel passage opening and said elongated means relative to each other in order to open and close the discharge opening.
 1. In an apparatus for steering a ship, the combination of a flow passage disposed in a bulb enlarGement which extends forwardly from the bow of the ship, the flow passage having one end opening on the surface of the hull at the bow of a ship to define an inlet channel for water, impeller means within said flow passage to generate a stream of water, two branch channel passages communicating with said flow passage downstream of said impeller means and each branch channel passage having an opening in the hull surface to discharge a stream of water therefrom, said branch channel passage converging toward its discharge opening, elongated means within each of said branch channel passages at the discharge openings thereof, and means for moving said converging branch channel passage opening and said elongated means relative to each other in order to open and close the discharge opening.
 2. In an apparatus as claimed in claim 1 wherein said elongated means comprises needle valve member which is hollow and is slidably supported on a fixed piston, and means for alternatingly introducing fluid under pressure on both sides of said piston within said valve member to move the same.
 3. In an apparatus as claimed in claim 1 wherein the longitudinal axes of the branch passages each defines an acute angle with the axis of rotation of the impeller means when projected on both a vertical plane which is perpendicular to said axis of rotation and a horizontal plane parallel to the axis of rotation. 